Air Conditioning (A/C) System Performance Test. Chevrolet Express 2001

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2001 🢒 Express 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Air Conditioning (A/C) System Performance Test

Table 1:	A/C Performance Table -- with Front A/C
Table 2:	A/C Performance Table -- with Rear A/C

This test measures the operating efficiency of the A/C system under the following conditions:

•	The current ambient air temperature

•	The current relative humidity

•	The high side pressure of the A/C system

•	The low side pressure of the A/C system

•	The temperature of the air being discharged into the passenger compartment

Test Description

The numbers below refer to the step numbers on the diagnostic table.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

This step measures the performance of the A/C system.

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

Important:

•	The ambient air temperature must be at least 16°C (60°F) .

•	Do not induce additional air flow across the front of the vehicle during the test.

•	If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
Turn OFF the ignition.
Install the J 43600 .
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures within the specified value?

More than 16°C (60°F), 345 kPa (50 psi)

More than 24°C (75°F), 483 kPa (70 psi)

More than 33°C (90°F), 690 kPa (100 psi)

Go to Step 2

Go to Leak Testing

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the drivers door window 12.7 15.2 cm (5-6 inches).
Select the following HVAC control settings:

•	The A/C is ON

•	The maximum blower speed

•	The Vent mode

•	The coldest temperature setting

•	All A/C outlets are OPEN

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in one of the following positions:

•	On an automatic, place vehicle in PARK

•	On a manual, place vehicle in NEUTRAL

Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Press the RESET button, before using the print function of the J 43600 .

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures to the table below.

Does all the data recorded fall within the specified ranges of the table below?

Go to Step 4

Go to Step 3

If the pressures and temperatures recorded do not fall within the specified ranges:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the table below.

Does all the data recorded fall within the specified ranges of the table below?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 5

Is the low side pressure greater than the specified range, but the high side pressure within or less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone B

Go to Step 6

Are the low and high side pressures both greater than the specified ranges?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone C

Go to Step 7

Is the high side pressure greater than the specified range, but the low side pressure is within or less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 8

Operate the system in order to verify the test results.

Did you find the same results?

System OK

Go to Symptoms - HVAC Systems - Manual

A/C System Pressure -- Zone Classification

A/C Performance Table -- with Front A/C

Ambient Air Temperature	Relative Humidity	Service Port Pressure		Maximum Left Center Discharge Air Temperature
Ambient Air Temperature	Relative Humidity	Low Side	High Side	Maximum Left Center Discharge Air Temperature
13-16°C (55-65°F)	0-100%	175-192 kPa (25-28 psi)	500-840 kPa (73-122 psi)	6°C (43°F)
19-24°C (66-75°F)	Below 40%	175-207 kPa (25-30 psi)	720-1090 kPa (105-158 psi)	6°C (43°F)
19-24°C (66-75°F)	Above 40%	175-232 kPa (25-34 psi)	740-1120 kPa (107-163 psi)	8°C (46°F)
25-29°C (76-85°F)	Below 35%	175-238 kPa (25-35 psi)	1000-1320 kPa (145-192 psi)	9°C (48°F)
	35-60%	175-244 kPa (25-35 psi)	1010-1330 kPa (147-193 psi)	9°C (48°F)
	Above 60%	175-257 kPa (27-37 psi)	1020-1360 kPa (148-197 psi)	11°C (52°F)
30-35°C (86-95°F)	Below 30%	190-279 kPa (28-41 psi)	1230-1590 kPa (179-231 psi)	12°C (54°F)
	30-50%	196-282 kPa (28-41 psi)	1240-1610 kPa (180-234 psi)	12°C (54°F)
	Above 50%	204-286 kPa (30-42 psi)	1250-1640 kPa (181-238 psi)	13°C (55°F)
36-41°C (96-105°F)	Below 20%	235-322 kPa (34-47 psi)	1500-1860 kPa (218-270 psi)	15°C (59°F)
	20-40%	237-320 kPa (34-47 psi)	1510-1880 kPa (219-273 psi)	15°C (59°F)
	Above 40%	240-318 kPa (35-47 psi)	1520-1900 kPa (221-276 psi)	16°C (61°F)
42-46°C (106-115°F)	Below 20%	283-359 kPa (41-52 psi)	1770-2090 kPa (257-303 psi)	18°C (64°F)
42-46°C (106-115°F)	Above 20%	282-353 kPa (41-51 psi)	1780-2110 kPa (235-306 psi)	18°C (64°F)
47-49°C (116-120°F)	Below 30%	319-377 kPa (46-55 psi)	2010-2240 kPa (292-325 psi)	20°C (68°F)

A/C System Pressure -- Zone Classification

A/C Performance Table -- with Rear A/C

Ambient Air Temperature	Relative Humidity	Service Port Pressure		Maximum Discharge Air Temperature
Ambient Air Temperature	Relative Humidity	Low Side	High Side	Left Center	Rear Center
13-18°C (55-65°F)	0-100%	175-205 kPa (25.4-29.8 psi)	420-860 kPa (61-124.8 psi)	6°C (42.8°F)	9°C (48.2°F)
19-24°C (66-75°F)	Below 40%	175-240 kPa (25.4-34.8 psi)	610-1080 kPa (88.5-156.7 psi)	8°C (46.4°F)	11°C (51.8°F)
19-24°C (66-75°F)	Above 40%	175-267 kPa (25.4-38.8 psi)	680-1170 kPa (98.7-169.8 psi)	10°C (50°F)	13°C (55.4°F)
25-29°C (76-85°F)	Below 35%	184-284 kPa (26.7-41.2 psi)	940-1330 kPa (136.4-193 psi)	11°C (51.8°F)	14°C (57.2°F)
	35-50%	197-293 kPa (28.6-42.5 psi)	990-1360 kPa (143.7-197.4 psi)	12°C (53.6°F)	15°C (59°F)
	Above 50%	207-310 kPa (30-45 psi)	1020-1430 kPa (148-207.5 psi)	13°C (55.4°F)	16°C (60.8°F)
30-35°C (86-95°F)	Below 30%	233-339 kPa (33.8-49.2 psi)	1210-1640 kPa (175.6-238 psi)	15°C (59°F)	18°C (64.4°F)
	30-50%	241-348 kPa (35-50.5 psi)	1240-1680 kPa (180-243.8 psi)	16°C (60.8°F)	19°C (66.2°F)
	Above 50%	253-362 kPa (36.7-52.5 psi)	1280-1730 kPa (185.8-251.1 psi)	18°C (64.4°F)	21°C (69.8°F)
36-41°C (96-105°F)	Below 20%	289-392 kPa (41.9-56.9 psi)	1520-1940 kPa (220.6-281.6 psi)	19°C (66.2°F)	21°C (69.8°F)
	20-40%	294-399 kPa (42.7-57.9 psi)	1540-1980 kPa (223.5-287.4 psi)	20°C (68°F)	22°C (71.6°F)
	Above 40%	303-407 kPa (44-59.1 psi)	1580-2010 kPa (229.3-293.7 psi)	21°C (69.8°F)	24°C (75.2°F)
42-46°C (106-115°F)	Below 20%	348-440 kPa (50.5-63.9 psi)	1840-2210 kPa (267.1-320.8 psi)	23°C (73.4°F)	24°C (75.2°F)
42-46°C (106-115°F)	Above 20%	352-446 kPa (51.1-64.7 psi)	1860-2240 kPa (270-325.1 psi)	24°C (75.2°F)	26°C (78.8°F)
47-49°C (116-120°F)	Below 30%	400-472 kPa (58.1-68.5 psi)	2130-2380 kPa (309.1-345.4 psi)	25°C (77°F)	27°C (80.6°F)